This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 6 |
| 5 | 30 |
| 6 | 30 |
| 7 | 210 |
| 8 | 630 |
| 9 | 2310 |
| 10 | 2310 |
| 11 | 25410 |
| 12 | 25410 |
| 13 | 330330 |
| 14 | 330330 |
| 15 | 330330 |
| 16 | 690690 |
| 17 | 11741730 |
| 18 | 11741730 |
| 19 | 223092870 |
| 20 | 223092870 |
| 21 | 223092870 |
| 22 | 223092870 |
| 23 | 5131136010 |
| 24 | 5131136010 |
| 25 | 26548051530 |
| 26 | 26548051530 |
| 27 | 80090340330 |
| 28 | 80090340330 |